Helen Fisher (born 1945) is an anthropology professor and human behavior researcher at the Rutgers University and is one of the major researchers in the field of interpersonal chemistry.[1][2][3] Prior to becoming a research professor at Rutgers University, she was a research associate at the American Museum of Natural History in New York City.

By many accounts, including her own, Fisher is considered the world’s leading expert on the topic of love.[4] Presently, Fisher is the most referenced scholar in the love research community. In 2005, she was hired by match.com to help structure the chemistry.com pair-matching website using both hormonal-based and personality-based matching techniques. She was one of the main speakers at the 2006 TED (conference).

Generally love will start off in the lust phase, strong in passion but weak in the other elements. The primary motivator at this stage is the basic sexual instinct. Appearance, smells, and other similar factors play a decisive role in screening potential mates. However, as time passes on
, the other elements may grow and passion may shrink — this depends upon the individual. So what starts as infatuation or empty love may well develop into one of the fuller types of love. At the attraction stage the person concentrates their affection on a single mate and fidelity becomes important.

Likewise, when a person has known a loved one for a long time, they develop a deeper attachment to their partner. According to current scientific understanding of love, this transition from the attraction to the attachment phase usually happens in about 30 months. After that time, the passion fades, changing love from consummate to companionate, or from romantic love to liking.

Similarly, according to psychologist many see love as being a combination of companionate love and passionate love. Passionate love is intense longing, and is often accompanied by sexual arousal (shortness of breath, rapid heart rate). Companionate love is affection and a feeling of intimacy not accompanied by physiological arousal.

Both men and women use physical attractiveness as a measure of how 'good' another person is. Men often tend to value attractiveness more than women. In fMRI brain scans published in 2004 by Rutgers University evolutionary anthropologist Helen Fisher, in the early intense stages of falling in love, there were clear differences in male and female brains[5]. Men, on average, tended to show more activity in two regions in the brain: one was associated with the integration of visual stimuli, and the second was with penile erection. Conversely, women in these early stages exhibited increased activity in several regions of the brain associated with memory recall. Fisher speculated the evolutionary source was in the need for females to identify males whose behavior over time suggested they would help the female raise her offspring. However, in terms of behavior, some studies suggest little difference between men and women. Symmetrical men and women begin to have sexual intercourse earlier, have more sexual partners, engage in a wider variety of sexual activities and have more casual sex.

↑Caravanos, Adelle. (2006). “Love: What’s Science Got to do with It? – Anthropologist Helen Fisher has a new theory about the chemical roots of romance.” Science & the City – Webzine of the New York Academy of Sciences. Feb. 12.